Method for signalling connection control part message loop prevention

Abstract

A method (100) for preventing message looping in a telecommunications network (70) includes the steps of receiving a UDT/S query message, determining a next destination for processing the query message and a route for delivering the query message to the next destination (102). A determination is then made as to whether the route to the next destination is XUDT/S capable (104). The UDT/S query message is converted to an XUDT/S format by inserting a hop counter (38) therein if the route is XUDT/S capable (108). The query message is then delivered to the next destination via the route (110). The hop counter (38) in the query message is then decremented at the next destination in response to receiving a message of the XUDT/S format (112). A message loop error is recognized and processed when the hop counter (38) reaches a predetermined value.

What is claimed is: 
     
       1. A method for preventing message looping in a telecommunications network, comprising the steps of: receiving a unit data service (UDT/S) query message;   determining a next destination for processing the query message and a route for delivering the query message to the next destination;   determining whether the route to the next destination is extended unit data service (XUDT/S) capable;   converting the UDT/S query message to an XUDT/S format by inserting a hop counter therein in response to the route being XUDT/S capable;   delivering the query message to the next destination via the route;   decrementing the hop counter in the query message at the next destination in response to receiving an XUDT/S message; and   recognizing and processing a message loop error in response to the hop counter reaching a predetermined value.   
     
     
       2. The method, as set forth in claim 1, wherein the message loop error processing step comprises the step of discarding the query message. 
     
     
       3. The method, as set forth in claim 1, wherein the step of converting the query message further comprises the step of initializing the hop counter to a predetermined initial value. 
     
     
       4. The method, as set forth in claim 1, wherein the step of converting the query message further comprises the step of modifying a value in a message type field therein to indicate an XUDT/S message format. 
     
     
       5. The method, as set forth in claim 1, wherein the step of determining a route to the next destination comprises the step of identifying a link set in the route immediately preceding the next destination. 
     
     
       6. The method, as set forth in claim 5, wherein the step of determining whether a route is XUDT/S capable comprises the step of determining the link set in the route immediately preceding the next destination is XUDT/S capable. 
     
     
       7. The method, as set forth in claim 1, further comprising the steps of: receiving an XUDT/S query message;   determining a next destination for processing the XUDT/S query message and a route for delivering the query message to the next destination; and   converting the XUDT/S query message to a UDT/S query message in response to determining the route being not XUDT/S capable.   
     
     
       8. A method for preventing message looping in a telecommunications network, comprising the steps of: receiving a query message;   determining a next destination for processing the query message and a route for delivering the query message to the next destination;   determining whether the route to the next destination is extended unit data service (XUDT/S) capable;   determining whether the query message is an XUDT/S message;   converting the query message to an XUDT/S message by inserting a hop counter therein in response to the route being XUDT/S capable and the query message not being an XUDT/S message;   converting the query message to a unit data service message by removing the hop counter therein in response to the route not being XUDT/S capable and the query message being an XUDT/S message;   delivering the query message to the next destination via the route;   decrementing the hop counter in the query message at the next destination in response to receiving an XUDT/S message; and   Discarding the query message in response to the hop counter reaching a predetermined value.   
     
     
       9. The method, as set forth in claim 8, wherein the step of converting the query message to an XUDT/S message further comprises the step of initializing the hop counter to a predetermined initial value. 
     
     
       10. The method, as set forth in claim 8, wherein the step of converting the query message to an XUDT/S message further comprises the step of modifying a value in a message type field therein to indicate an XUDT/S message format. 
     
     
       11. The method, as set forth in claim 8, wherein the step of determining a route to the next destination comprises the step of identifying a link set in the route immediately preceding the next destination. 
     
     
       12. The method, as set forth in claim 11, wherein the step of determining whether a route is XUDT/S capable comprises the step of determining the link set in the route immediately preceding the next destination is XUDT/S capable.